The need for a protected light path, especially in the field of photography, exists even today in the electronic age. This has been previously accomplished with the traditional three-layer, laminated bellows or hoods (see, e.g., U.S. Pat. No. 3,191,513), the telescoping bellows and the constructions. Each of these construction types have had their advantages and limitations.
In particular, the conventional three-layered laminated bellows constructions which typically consisted of a stiffening paper skeleton or grid sandwiched between two plies to flexible sheet material used to be made with cotton-based fabrics. However, due to their tendency to deteriorate, these cotton-based fabrics have been replaced with nylon which, together with calendered coatings of crude rubber and urethane, have extended product lifetimes beyond fifteen years and 6.times.10.sup.5 operating cycles (i.e., extension and contraction of the bellows or hood). Despite this fact, the units are still assembled and glued by hand, placed in a rotary press and manually folded. Delamination and sloppy seams continue to be quality problems for this construction.
The other aforementioned types of bellows constructions also have significant disadvantages. The telescoping bellows, for example, have poor extension to compression ratios, are subject to temperature expansion and jamming, and require costly molds. The vacuum-formed constructions have low operational lifetimes and require costly molds as well.
It is therefore an object of the present invention to provide a novel method for producing bellows and, in particular, camera and enlarger bellows and hoods, which is relatively simple and yet highly effective.
It is a further object of the present invention to produce such a novel method which is fast and efficient and which reduces the number of manual operations.
It is another object of the present invention to provide such a method having the foregoing attributes and characteristics which produces a bellows construction which is reliable, durable and relatively inexpensive.